1 . Technical Field
The present invention relates generally to dentifrices, and more particularly to dentifrice compositions containing enhanced levels of minerals for mineralizing and remineralizing teeth, as well as various chemical compounds for promoting beneficial oral cavity health.
2 . Discussion
A dentifrice is a substance or preparation used with a toothbrush to aid mechanical cleaning of the accessible surfaces of the teeth. A typical formulation for a dentifrice (e.g., toothpaste) contains varying amounts of humectants (e.g., glycerine, sorbital, propylene glycol, xylitol, polyethylene glycol), water, buffers/salts/tartar controls (e.g., tetrasodium pyrophosphate, sodium tripolyphosphate), organic thickeners and gums (e.g., sodium carboxylmethyl cellulose, cellulose ethers, xanthan gum, carrageenans, sodium alginate, and carbopols), inorganic thickeners (e.g., silica thickeners, sodium aluminum silicates, and clays), abrasives (e.g., hydrated silica, dicalcium phosphate digydrate, calcium carbonate, sodium bicarbonate, calcium pyrophosphate, and alumina), active ingredients (e.g., fluoride, and TRICLOSAN(trademark)), surfactants (e.g., sodium lauryl sulfate, sodium N-lauryl sarcosinate, pluronics, sodium lauryl sulfoacetate), and flavors and sweeteners (e.g., wintergreen, cinnamon, peppermint, etc.).
On the basis of clinical studies involving the use of dentifrices containing sodium monofluorophosphate, Na2PFO3, as the active ingredient have been accepted by the Council on Dental Therapeutics of the American Dental Association (ADA) as effective in helping to prevent caries. Examples of dentifrices containing sodium monofluorophosphate are Colgate with MFP and Macleans Fluoride. When incorporated in dentifrice formulations at a level of ca. 0.76%, sodium monofluorophosphate has been shown to be of benefit in 17-38% reduction of dental caries. These findings are in the same general range as those reported for dentifrices already accepted by the ADA that contain 0.4% stannous fluoride (SnF2) (e.g., Crest and Aim).
In addition to the prevention of caries, there has been increasing interest by the dental health industry in the mineralization and remineralization of tooth enamel. Enamel is the term given to the bony outer surface of teeth. Enamel, as well as other structures of the tooth (e.g., dentin), are generally comprised of apatite (e.g., calcium phosphate in the form of calcium hydroxyapatite). Through malnutrition, disease, neglect, and certain dental procedures (e.g., bleaching), the tooth enamel can become demineralized and, as a result, subject to decay, thus leading to the formation of caries, lesions or cavities. For example, the consumption of sugary foods and beverages tends to enable the proliferation of plaque bacteria which in turn produces an acidic environment in the mouth which eventually leads to the demineralization of the tooth, absent appropriate intervention. The mode of demineralization is thought to involve the highly increased solubility of calcium phosphate salts in acidic oral cavity environments, as opposed to the high insolubility of calcium phosphate salts in normal pH oral cavity environments.
Although saliva, which is supersaturated with calcium and phosphate ions, aids somewhat in the natural remineralization process of enamel and dentin, it is a very slow process (due, in part, to the low solubility of calcium phosphate at the pH of saliva) whose benefits can be overcome in persistently acidic oral cavity environments. It is generally known that fluoride ions can enhance the natural remineralization process, thus, this is the reason why many commercially available dentifrices now contain various forms of fluoride ions, e.g., in the form of stannous fluoride or sodium monofluorophosphate.
One readily commercially available product that supposedly addresses the issue of mineralization and remineralization of various surface and subsurface tooth structures, such as enamel and dentin, is marketed under the tradename ENAMELON(trademark) and is manufactured by Enamelon, Inc. (Cranbury, N.J.). With respect to ENAMELON(trademark) brand dentifrice, the manufacturer claims that it contains a source of calcium ions, a source of phosphate ions, and a source of fluoride ions that act in manner that promotes the mineralization/remineralization of various surface and subsurface tooth structures, such as the enamel and the dentin.
A more complete discussion of tooth mineralization and remineralization can be found in the following U.S. patents, the entire specifications of which are incorporated herein by reference:
U.S. Pat. No. 4,083,955 discloses that two compositions containing respectively a cation and an anion, such as calcium ion and phosphate ion, are sequentially applied to dental enamel resulting in remineralization of subsurface dental enamel.
U.S. Pat. No. 4,327,079 discloses a dentifrice composition containing synthetic hydroxyapatite powder which is neutral or weakly alkaline or contains 0.1 to 20% by weight of NaCl and/or KCl and 0.003 to 3% by weight of MgCl2.
U.S. Pat. No. 4,356,168 discloses an opacified dental cream which effects dental remineralization and reduces caries formation.
U.S. Pat. No. 4,357,317 discloses a dental cream composition containing a binary fluorine providing system which provides about 1000-1670 ppm (0.1-0.16% by weight) fluorine from sodium monofluorophosphate and sodium fluoride wherein sodium fluoride provides about 30-35% by weight of the fluorine in amount of about 300-580 ppm (0.02-0.058% by weight).
U.S. Pat. No. 4,397,837 discloses compositions for the remineralization and prevention of demineralization of the teeth of animals including humans in the form of two phases, one phase containing a water-soluble calcium compound and the other phase containing a water-soluble phosphate and optionally a water-soluble fluorine compound.
U.S. Pat. No. 4,425,324 discloses a hazed toothpaste which can effect dental remineralization and reduce caries formation.
U.S. Pat. No. 4,460,565 discloses a dentifrice containing two or more fluorine compounds, at least one soluble salt producing phosphate ions, and at least one substance providing calcium ions, and as a result thereof having good remineralization properties.
U.S. Pat. No. 4,518,430 discloses compositions that are remineralizers and dental cements, as well as methods for their use.
U.S. Pat. No. 4,606,912 discloses solutions for optimizing the environmental conditions within the human oral cavity which enhances the functioning of cells of the oral cavity and promotes remineralization of teeth.
U.S. Pat. No. 5,571,502 discloses non-aqueous compositions and methods utilizing same which are useful to remineralize subsurface dental enamel.
U.S. Pat. No. 5,603,922 discloses remineralization, without demineralization, by applying to the teeth a composition which is present in either one or in two phases and which does not react to any large extent until introduced into the oral cavity and upon such introduction does not rapidly precipitate.
U.S. Pat. No. 5,605,675 discloses the remineralization of dental enamel by applying to the teeth a composition which is present in two phases which do not react with one another until introduced into the oral cavity.
U.S. Pat. No. 5,605,677 discloses a toothpaste containing typical components and a combination of silicas and dicalcium phosphate dihydrate (brushite) as its polishing component provides for particularly good restoration of the surface of teeth.
U.S. Pat. No. 5,614,175 discloses non-aqueous compositions and methods utilizing same which are useful to remineralize subsurface dental enamel.
U.S. Pat. No. 5,618,549 discloses a method of treating a living organism having a disease associated with demineralization or mineralization defects of an existing bone by applying in a spongy portion of the bone or in a medullary canal of the bone at least one biocompatible and bioabsorbable calcium salt in the form of particles having dimensions less than 8 mm.
U.S. Pat. No. 5,645,853 discloses chewing gum compositions and methods utilizing same which are useful to remineralize surface dental enamel.
U.S. Pat. No. 5,817,296 discloses remineralization, without demineralization, by applying to the teeth a composition which is present in either one or in two phases and which does not react to any large extent until introduced into the oral cavity and upon such introduction does not rapidly precipitate.
U.S. Pat. No. 5,833,954 discloses anticarious delivery vehicles, specifically chewing gums, candies, confectioneries, toothpastes, dentifrices and gels.
U.S. Pat. No. 5,833,957 discloses remineralization, without demineralization, by applying to the teeth a composition which is present in either one or in two phases and which does not react to any large extent until introduced into the oral cavity and upon such introduction does not rapidly precipitate.
U.S. Pat. No. 5,853,704 discloses a multicomponent anticaries dentifrice composition and method of use therefore, having a first dentifrice component containing a fluoride ion source and a second dentifrice component containing a casein glycomacropeptide compound, wherein the components are physically separated before use and are combined immediately prior to application to the teeth, the dentifrice exhibiting enhanced enamel remineralization.
U.S. Pat. No. 5,858,333 discloses a two-part oral product capable of remineralizing subsurface lesions and/or mineralizing exposed dentinal tubules in teeth is composed of cationic and anionic discrete parts.
U.S. Pat. No. 5,895,641 discloses remineralization, without demineralization, of dental enamel by applying to the teeth a composition which is present in two phases which do not react with one another until introduced into the oral cavity.
U.S. Pat. No. 5,958,380 discloses a stable, single-part chewing gum product and methods of using same to effect remineralization of subsurface lesions in teeth and/or mineralization of exposed dentinal tubules.
U.S. Pat. No. 5,993,786 discloses anticarious delivery vehicles, specifically chewing gums, candies, confectioneries, toothpastes, dentifrices and gels.
U.S. Pat. No. 6,036,944 discloses a method for remineralizing one or more subsurface lesions in a tooth and/or mineralizing one or more exposed dentinal tubules in the tooth involves dispensing effective amounts of at least one water-soluble calcium salt, at least one water-soluble non-toxic divalent metal compound wherein the divalent metal is other than calcium, at least one water-soluble phosphate salt and, optionally, a water-soluble fluoride salt; mixing the salts and compound to form a non-carbonated mixture having a pH in water such that a non-carbonated aqueous solution containing the mixture has a pH of from 4.5 to about 7.0; and then applying the non-carbonated mixture as the non-carbonated aqueous solution to a surface of the tooth for a sufficient period of time to allow sufficient amounts of calcium, phosphate and, if present, fluoride, ions in the solution to diffuse into the subsurface of the tooth where the diffused ions then react to form an insoluble precipitate onto the lesions and/or exposed tubules, thereby remineralizing the lesions and/or mineralizing the tubules.
Although various dentifrice products that are currently available on the market appear to address the need for mineralization and remineralization of teeth, they do not address the need to provide for proper oral cavity health, including the protection of gum tissues from various diseases. The prevalence of various diseases that adversely affect gum tissues, such as gingivitis and periodontal disease, has lead to severe health consequences for many individuals, including the loss of their teeth and other related health problems. Although the aforementioned mineralization and remineralization of teeth aids somewhat in the overall health of the oral cavity, the need for proper care of the surrounding tissues, most notably the gums, must not be overlooked.
Therefore, there exists a need for dentifrice compositions containing enhanced levels of minerals for mineralizing and remineralizing teeth, as well as various chemical compounds for promoting beneficial oral cavity health.
Accordingly, it is an object of the present invention to provide a new and improved dentifrice composition.
It is another object of the present invention to provide a new and improved dentifrice composition that has enhanced levels of minerals for mineralizing and remineralizing teeth.
It is still another object of the present invention to provide new and improved dentifrice compositions containing enhanced levels of minerals for mineralizing and remineralizing teeth, as well as various chemical compounds for promoting beneficial oral cavity health.
In accordance with one embodiment of the present invention, a dentifrice composition is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
at least one water soluble calcium salt;
at least one water soluble phosphate salt; and
at least one antioxidant.
In accordance with another embodiment of the present invention, a dentifrice composition is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
at least one water soluble calcium salt;
at least one water soluble phosphate salt;
at least one antioxidant; and
at least one selenium-containing material.
In accordance with yet another embodiment of the present invention, a dentifrice composition is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
at least one water soluble calcium salt;
at least one water soluble phosphate salt;
at least one antioxidant;
at least one selenium-containing material; and
at least one bromine-containing material.
In accordance with still another embodiment of the present invention, a method is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
providing at least one water soluble calcium salt;
providing at least one water soluble phosphate salt;
providing at least one antioxidant;
mixing said salts and antioxidant to form a mixture; and
applying said mixture to the tooth surface for a sufficient period of time to allow sufficient amounts of calcium and phosphate ions in the mixture to diffuse through the tooth surface, where the diffused ions react together to form an insoluble precipitate on the surface or subsurface of the tooth.
In accordance with still yet another embodiment of the present invention, a method is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
providing at least one water soluble calcium salt;
providing at least one water soluble phosphate salt;
providing at least one antioxidant;
providing at least one selenium-containing material;
mixing said salts, antioxidant, and material to form a mixture; and
applying said mixture to the tooth surface for a sufficient period of time to allow sufficient amounts of calcium and phosphate ions in the mixture to diffuse through the tooth surface, where the diffused ions react together to form an insoluble precipitate on the surface or subsurface of the tooth.
In accordance with a further embodiment of the present invention, a method is provided for mineralizing and remineralizing a surface or subsurface of at least one tooth, comprising:
providing at least one water soluble calcium salt;
providing at least one water soluble phosphate salt;
providing at least one antioxidant;
providing at least one selenium-containing material;
providing at least one bromine-containing material;
mixing said salts, antioxidant, and materials to form a mixture; and
applying said mixture to the tooth surface for a sufficient period of time to allow sufficient amounts of calcium and phosphate ions in the mixture to diffuse through the tooth surface, where the diffused ions react together to form an insoluble precipitate on the surface or subsurface of the tooth.
A more complete appreciation of the present invention and its scope can be obtained from understanding the following detailed description of the invention and the appended claims.
The present invention is primarily directed to dentifrice compositions, and particularly those dentifrice compositions containing enhanced levels of minerals for mineralizing and remineralizing teeth, as well as various chemical compounds for promoting beneficial oral cavity health.
In accordance with one aspect of the present invention, not only are enhanced levels of water soluble calcium salts and phosphate salts employed, but divalent metals, such as magnesium, strontium, tin, and zinc, are optionally employed as well. These divalent metals aid in the aforementioned mineralization and remineralization processes.
Water-soluble calcium salts and compounds suitable for practicing the present invention are, by way of a non-limiting example, calcium chloride, calcium bromide, calcium nitrate, calcium acetate, calcium gluconate, calcium benzoate, calcium glycerophosphate, calcium formate, calcium fumarate, calcium lactate, calcium butyrate and calcium isobutyrate, calcium malate, calcium maleate, calcium propionate, or mixtures of water-soluble calcium compounds. In the compositions of the invention for the mineralization/remineralization of human dental enamel, the calicum ions are preferably present in a range from about at least 18 mmol/L to about 1.5 mol/L.
Water-soluble inorganic phosphate salts and compounds suitable for practicing to the present invention are, by way of a non-limiting example, alkali salts and ammonium salts of orthophosphoric acid, such as potassium, sodium or ammonium orthophosphate, monopotassium phosphate, dipotassium phosphate, tripotassium phosphate, monosodium phosphate, disodium phosphate and trisodium phosphate. The concentration of the phosphate ions is preferably about at least 18 mmol/L to about 1.5 mol/L.
If desired, water-soluble salts yielding both calcium and phosphate ions, such as monobasic-calcium orthophosphate, may be employed.
With respect to the stabilizing divalent metal compound, it is also possible to employ any water-soluble, non-toxic divalent metal compound which will stabilize the calcium and phosphate ions so that they do not rapidly or prematurely precipitate before diffusing into the teeth. In practice, however, it has been found that at least one member selected from the group consisting of magnesium, strontium, tin, and zinc, with magnesium being preferred, are the most effective in stabilizing the system.
Suitable magnesium compounds are, by way of a non-limiting example, magnesium acetate, magnesium ammonium sulfate, magnesium benzoate, magnesium bromide, magnesium borate, magnesium citrate, magnesium chloride, magnesium gluconate, magnesium glycerophosphate, magnesium hydroxide, magnesium iodide, magnesium oxide, magnesium propionate, magnesium D-lactate, magnesium DL-lactate, magnesium orthophosphate, magnesium phenolsulfonate, magnesium pyrophosphate, magnesium sulfate, magnesium nitrate, and magnesium tartrate.
Suitable strontium compounds are, by way of a non-limiting example, strontium acetate, strontium ammonium sulfate, strontium benzoate, strontium bromide, strontium borate, strontium caprylate, strontium carbonate, strontium citrate, strontium chloride, strontium gluconate, strontium glycerophosphate, strontium hydroxide, strontium iodide, strontium oxide, strontium propionate, strontium D-lactate, strontium DL-lactate, strontium pyrophosphate, strontium sulfate, strontium nitrate, and strontium tartrate.
Suitable tin compounds are, by way of a non-limiting example, stannous acetate, stannous ammonium sulfate, stannous benzoate, stannous bromide, stannous borate, stannous carbonate, stannous citrate, stannous chloride, stannous gluconate, stannous glycerophosphate, stannous hydroxide, stannous iodide, stannous oxide, stannous propionate, stannous D-lactate, stannous DL-lactate, stannous orthophosphate, stannous pyrophosphate, stannous sulfate, stannous nitrate, and stannous tartrate.
Suitable zinc compounds are, by way of a non-limiting example, zinc acetate, zinc ammonium sulfate, zinc benzoate, zinc bromide, zinc borate, zinc citrate, zinc chloride, zinc gluconate, zinc glycerophosphate, zinc hydroxide, zinc iodide, zinc oxide, zinc propionate, zinc D-lactate, zinc DL-lactate, zinc pyrophosphate, zinc sulfate, zinc nitrate, and zinc tartrate. Preferred zinc compounds are zinc acetate, zinc chloride, zinc sulfate, and zinc nitrate.
The compositions of the present invention for the remineralization or prevention of demineralization of human teeth may also contain water-soluble fluoride compounds, the caries-prophylactic activity of which has for a long time been considered to be established. When two phase systems are employed, these compounds are preferably present in the phase containing phosphate in order to avoid the formation of sparingly soluble calcium fluoride.
Suitable fluoride compounds are the alkali fluorides such as, by way of a non-limiting example, sodium, potassium, lithium or ammonium fluoride, tin fluoride, indium fluoride, zirconium fluoride, copper fluoride, nickel fluoride, palladium fluoride, fluorozirconates such as sodium, potassium or ammonium fluorozirconate or tin fluorozirconate, fluorosilicates, fluoroborates, fluorostannites.
Organic fluorides, such as the known amine fluorides are also suitable for use in the compositions of the invention.
Water-soluble alkali metal monofluorophosphates such as sodium monofluorophosphate, lithium monofluorophosphate and potassium monofluorophosphate, preferably, sodium monofluorophosphate may be employed. In addition, other water-soluble monofluorophosphate salts may be employed including, by way of a non-limiting example, ammonium monofluorophosphate aluminum monofluorophosphate, and the like. If monofluorophosphate salts are used as the fluoride source in two-component systems, they could be present in the first component along with the calcium cations without departing from the present invention. However, this is less desirable due to the potential loss of fluoride.
Suitable toothpastes and gels can be made by employing, in addition to the mineralizing/remineralizing agents of the invention, from about 0.5% to 65%, preferably from about 5% to 40%, of an abrasive, from about 0.2% to 5% of a sudsing agent, from about 0. 1% to 5% of a binding agent, from 0% to 50% of a humectant, and the balance, water and other minor ingredients. From about 1.0% to 10.0% of an inorganic thickener such as hydrated silica may be added.
In the case of two separate components, the pH of a component of such toothpaste or gel comprised of the active cationic or anionic ingredients each has a pH of more than about 3. The mixture of the two portions which is placed in the mouth, however, must have a pH of from 4.5 to about 7.0, preferably from about 5.0 to about 7.0, more preferably from about 5.0 to about 5.75. The pHs of the cationic portion and the anionic portion can be adjusted so long as the above pH parameters are not exceeded.
Suitable abrasives include silica xerogels. Other conventional toothpaste abrasives can be used in the compositions of this invention, and include beta phase calcium pyrophosphate, dicalcium phosphate dihydrate, anhydrous calcium phosphate, calcium carbonate, zirconium silicate, and thermosetting polymerized resins. Silica aerogels and the insoluble metaphosphates such as insoluble sodium metaphosphate can be used. Mixtures of abrasives can also be used.
Suitable sudsing agents are those which are reasonably stable and form suds throughout the period of application. Preferably, non-soap anionic or nonionic organic synthetic detergents are employed. Non-limiting examples of such agents are water-soluble salts of alkyl sulfate having from 10 to 18 carbon atoms in the alkyl radical, such as sodium lauryl sulfate, water-soluble salts of sulfonated monoglycerides of fatty acids having from 10 to 18 carbon atoms, such as sodium monoglyceride sulfonate, salts of C10-C18 fatty acid amides of taurine, such as sodium N-methyl taurate, salts of C10-C18 fatty acid esters of isethionic acid, and substantially saturated aliphatic acyl amides of saturated monoaminocarboxylic acids having 2 to 6 carbon atoms, and in which the acyl radical contains 12 to 16 carbon atoms, such as sodium-N-lauryl sarcoside. Mixtures of two or more sudsing agents can be used.
A binding material is added to thicken and provide a desirable consistency for the present compositions. Suitable thickening agents are, without limitation, water-soluble salts of cellulose ethers, such as sodium carboxymethyl cellulose, hydroxypropyl cellulose, and hydroxyethyl cellulose. Natural gums such as gum karaya, gum arabic, carrageenan and gum tragacanth, can also be used. Colloidal magnesium aluminum silicate, silica aerogels, silica xerogels, fumed silica, or other finely divided silica can be used as part of the thickening agent for further improved texture. A preferred thickening agent is xanthan gum.
It is also desirable to include some humectant material in a toothpaste or gel to keep it from hardening. Suitable humectants include glycerine, sorbitol, polyethylene glycol, propylene glycol, and other edible polyhydric alcohols as well as mixtures thereof.
Toothpaste or gel compositions may also contain flavoring agents such as oil of wintergreen, oil of peppermint, oil of spearmint, oil of sassafras, and oil of clove, as well as cinnamon.
Toothpaste or gel compositions may further contain sweetening agents such as saccharin, dextrose, luvulose, sodium cyclamate, and aspartame. Mixtures of sugar with a sweetener, e.g., sucralose, are also envisioned.
In accordance with another aspect of the present invention, trace minerals, such as selenium and bromine, that are believed to have beneficial effects on the overall health of the oral cavity are also preferably employed in the dentifrice composition of the present invention. Although these trace minerals may be added to the dentifrice composition of the present invention from various chemical suppliers, it is preferred to use mineral water from a natural source, such as a spring. Examples of such naturally-occurring springs are located in the southeastern portion of Michigan, for example in the Mount Clemens area, and have been identified as having some of the highest, if not the highest, levels of naturally-occurring minerals, as well as trace minerals, of any springs in the world. Although the exact mechanisms of the health benefits have not been thoroughly explained, it is generally recognized that several different types of trace minerals, such as selenium and bromine, have been identified as having potentially beneficial effects on overall health, and specifically on the health of the oral cavity, either acting alone or in concert with other minerals, vitamins, and/or enzymes.